Not much......
Hydrogen gas is not toxic. Of course, if you were to breathe pure hydrogen you would soon suffer from lack of oxygen.
No.
They breathe air, which contains oxygen. They do not breathe hydrogen, as it is a bad idea to mix hydrogen and oxygen unless you intend to create anexplosion.
We Breathe in a mixture of Carbon, Hydrogen and Oxygen, and exhale Carbon Dioxide
No. The sun does not breathe as it is not alive. It is powered by the fusion of hydrogen at its core.
From what I know about chemical compunds, there is too much H (Hydrogen) in water for land animals to breathe as there is none in air, or close to it. Also, it doesn't include Argon or Nitrogen.For their counterpart, Water animals can not breathe air(Except for dolphins and lung fish) because they do not reach a sufficient amount of Hydrogen. That's my guess anyway.
because it doesn't have hydrogen in it. we should only breathe in H2O, in air form.
because when you use hydrogen, it kinda helps you breathe and it also is a gas. and oxygen and hydrogen make water to stay hydrated.
no it is completely different are bodies cant breathe that only pure oxygen(o2). although fish can breathe the dissolved oxygen in water
No. You are thinking of nitrogen.
photosynthesis and respiration (photosynthesis by plants let out oxygen, we breathe in oxygen and breathe out carbon dioxide)
No. Jupiter's atmosphere is mostly hydrogen and helium with no free oxygen.